Which of the following is false?

Which of the following is false ?
a) endotoxins can increase the virulence of a non invasive bacterium
b) endotoxins are required in large amounts to cause a disease
c) endotoxins cause the bacterial cell to lyse
d ) endotoxins are generally heat sensitive
Ans given in marrow notes is option c. That’s ok
But , aren’t endotoxins supposed to be heat stable .
Considering that , option d is also false na?